1. Field of the Invention
The present invention relates to Radio Frequency Identification (RFID) reader and, more particularly, to an enhanced mechanism for RFID reader.
2. Description of Related Art
RFID is suitable for use of tag and reader, which applies the technique of wireless radio waves to identify objects automatically. The frequency band of RFID includes low frequency (125 k-135 kHz), high frequency (13.56 MHz), ultra high frequency (UHF 860-930 MHz), microwave (2.45 GHz), etc. Characteristics of different frequencies have different applications. For the RFID of electromagnetic induction type, the antenna of the reader continuously emits electromagnetic pulses, and the antenna coil of the RFID tag uses magnetic field to produce electric currents. The drive chip induces a coupling effect to start a certification process, which transfers the stored information to the reader within an operative distance. Then, the reader will transform and transfer the received information to an edge server to be encoded and processed. Therefore, RFID technique can be applied in a tracing device for merchandise management. For example, if the merchandises pass through the effective area of a special scanning device, the RFID reader will be able to locate its exact position.
As shown in FIG. 1, when merchandises pass through the entrance of a building, antenna 15 can receive the RFID signal reflected by the RFID tag 14 on the subject, and then it outputs the received RFID signal to a RFID reader 16. However, the RFID signal reflected by the RFID tag 14 on the object is passive, so the signal is weak. If the transmission distance is too long, or the RFID tag is attached to a dead space, both cases will result in the situation of ineffective RFID signal identification. Therefore, it is desired to provide an effective RFID signal receiver to mitigate and/or obviate the aforementioned problems.